Glass Formation in Hybrid Organic‐Inorganic Perovskites

Crystalline materials have governed the development of hybrid organic‐inorganic perovskites (HOIPs), giving rise to a variety of fascinating applications such as solar cells and optoelectronic devices. With increasing interest in non‐crystalline systems, the glassy state of HOIPs has recently been identified. Here, the basic building blocks of crystalline HOIPs appear to be retained, though their glasses lack long‐range periodic order. The emerging family of glasses formed from HOIPs exhibits diverse properties, complementary to their crystalline state. This mini review describes the chemical diversity of both three‐dimensional and two‐dimensional crystalline HOIPs and demonstrates how glasses are produced from these materials. Specifically, current achievements in melt‐quenched glasses formed from HOIPs are highlighted. We conclude with our perspective on the future of this new family of materials. The glassy state of hybrid organic‐inorganic perovskites (HOIPs) has recently been identified, exhibiting diverse properties complementary to the crystalline state. This mini review presents an overview of the structural chemistry of both two‐dimensional and three‐dimensional HOIPs, and a comprehensive discussion on their glass formation processes. Current advances in melt‐quenched glasses formed from HOIPs are discussed, and an outlook for the future of this new family of materials is offered.